Car coupling mechanism



Dec. 20, 1932. C, H, TQML|NS0N 1,891,660

CAR COUPLING MECHANISM Filed March 17. 1930 s sheets-sheet 1 Dec. 20, 1932.

C. H. TOMLINSON GARI COUPLING MECHANISM Filed March l? 1930 3 Sheets-Sheet 2 Inventor.'

By /a/we,

A tlor ney Dec. 20, 1932. C, H, TQMUNSON 1,891,660

CAR COUPLING MECHANI SM Filed March 17. 1930 5 Sheets-Sheet 3 Patented Dec. 240, 1932 entran srarss PATENT FFH:

CHARLES H. TOMLINSON, OIE* MASFELD, OHIO, ASSIGNOR- T THE TOMLINSON C'OUPLER i COMPANY, 0F MANSFIELD, OHIO, A CORPORATION 0F OHO cnn COUPLING MECHANISM Appncamn sied Marchi?, 1930. serial No. 436,638.

This invention relates to mechanism for joining ends of cars in a train and has for one of its objects the provision of coupling mechanism which will minimize the possibility` of errors in operation resulting from the human element. y f

A further object is toprovidemeans for compelling correct operation of the coupling mechanism by the trainmen.

A further object is to provide means for requiring the coupling mechanism to vbe properly connected before the train can move.

A further obj ect is to compel the knuckles of the couplers to bein open position on both ends of a train, ready to couple by impact at all times. y

A further object is to provide means for controlling the air and steam lines of the coupled train. Other objects and advantages will appear from the following description.

The invention is exemplified in the com# bination and arrangement of parts shownzin the accompanying drawings and described in the following specification, and it is more particularly pointed out in the append-ed claims.

This application is in part a continuation of application, Serial Number 219,667, filed September 15, 1927.

In the drawings:

Fig. l isa horizontal, sectional, somewhat diagrammatic view of one form of coupler having the present invention applied thereto.

Fig. 2 is a side elevation of the coupler shown in Fig. 1.

Fig. 3 is. a View similar to Fig. 1 showing the coupling knuckle. open. y

Fig. 4 is a frontl elevation of the coupler shown in 1 with parts broken away.

Fig. 5 is a fragmentary sectional view showing a detail of construction.

Fig. 6 is a view similar to Fig. 1 showing a somewhat modiiied form of the invention.

Fig. 7 is a: view similar to Fig. 1 showing still another adaptation of the invention.

Fig. 8 is a vertical sectional view of a bufing platform showing the application of one element of the invention thereto.

Fig. 9 is a 7iew 'similar'to F ig. 8 but showingthe bufng platform contacting with the Y buiiing platform of a coupled car.V

Fig. 10 isa side elevation of the coupler headon a larger scale than that of the other `figures, with parts in section..l

Fig. 11 is a view similar to Fig. 7 sho-wing another form ofthe invention.

Forl safe operation of a train of cars, it is of prime importance that the, air brake line shall be properly connected to provide communication from the engineers cab througho ut the entire train. The automatic air brake line is commonly provided with al cut-out or angle cock at each vend of each car and when two cars are coupled together, these valves must be opened to insure operation of the air brakes,'for if any one of these valves is left closed, the engineer is powerless to operate the air brakes inthe cars behind the closed 7 valve. It is a usual practicey in railroading, after a passenger train has been made up, for the engineer to apply the brakes and for the attend ants on the train to examine the brakes and see if they properly operate. 'If a cutout cock is left closed at any placein the train andthe attendant fails to note that the brakes do not operate and to signal the engineer to this efect,'there is nothing to apprise the engineerthat he is unable to operate his brakes until he tries the brakes while the trainis in motiong If, then, the

brakes fail to operate, he knows that some-v thing is vwrong but this may b-e too late to save .the lives and property in his charge. Disastrous wrecks have occurred because a single cut-outl cock was left closed after thetrain had been coupled up.

The present invention provides means for setting the brakes of the train so thatit is impossible to release the brakes and move the train if any one of the cut-out cocks is left closed Vafter the train has been coupled, or

Y The present .invention provides automatic coupling mechanism for the steam line p1pes,

thus avoiding the necessity of flexible hose couplings between the cars. It also provides means for draining any condensed moisture from the rear end of the trailing car, thus insuring live steam throughout the entire steam line and avoiding freezing of water in any part of the line.

In the embodiment of the invention illustrated in F iO's. 1 to 5, inclusive, the invention is illustrated as applied to a coupling similar to that shown in my prior Patent No. 1,660,733 dated February 28, 1928.

A draw bar 12 carries the coupler head provided with lateral projections 13 and 111 having a pin 15 and a socket 16, respectively, for'engaging complementary portions of a co-operating coupler. A knuckle 17 of the Janney type is pivoted at 18 in the coupler head and is provided with a tail piece 19 which is engaged by a lock 2O for holding the'knuckle in closed position. A spring 21 urges the lock 20 into locking position. A

s rinheld lunffer 22Ven raf1es the tail 19 b C l? to swing the knuckle open when released by the lock 20. lWhen the knuckle is in its open position, as shown in Fig. 3, the tail piece is engaged by the lock 2O to hold the knuckle open in position to be engaged by the knuckle of a complementary coupler and forced to closed position on impact of the cars. The plunger 22 alsov acts as a safety device for preventing displacement of the knuckle 17 in case the pin 18 should break or be sheared. It will be seen that the lock has a wedging surface which engages the tail piece 19 and draws the knuckle 17' into tight engagement with the co-operating knuckle so that a tight-docking coupler is provided, as explained and claimed in my prior patent, referred to above. The present invention, however, is applicable to any form of coupler, as will be explained later.

The brakeline pipe shown at 23 is provided with a spring-pressed buttend contact 24,

' shown more clearly in Fig. 10. The end of the brake line pipe is open so that connection is made with the brake pipe of an adjacent car upon impact of the cars. The brake line pipe. 23 is provided with a cut-out cock 25 yfor opening and closing the brake line relative to the automatic brake pipe coupler. The cut-out cock may be connected with a drum switch 26 for controlling the electrical circuits through the car shown at 27, and for interlocking the brake line pipe and electrical circuits so that the circuits will be closet at the same time that the brake line is opened; The brake line 23 is provided with la branch pipe 28 which is controlled by a cock 29 also connected to the drum switch 26 and arrange-d to open the branch pipe 28 when the cock 25 is closed and to close the branch pipe 28 when the cock 25 is open. The cocks 25 and 29 may be directly connected or connected by other means than the switch 26 where conditions require.

The branch pipe 28 is connected to a valve chamber 30 supported on the coupler head, as shown in Figs. 2 and 5. A spring-held valve 31 is arranged within the casing 30 t0 close the branch pipe 28. The valve 31 is provided with a projecting stem 32 having the end thereof rounded. The stern 32 projects into the coupler head in the path of the tail piece 19. .The tail piece 19 is provided with a cam face 33, so that when the tail piece is swung to its closed position, it will engage the rounded end of the stem 32 and force the stem inwardly, thus opening the valve 31 and providing communication for the branch pipe 28 with the atmosphere. When the knuckle 17 is open, the end of the stem 32 will be cleared so that the valve is free to be closed and being biased to closed position by its spring it will automatically close as soon as the knuckle has moved sufliciently to clear the stem 32. The lock 2O for the knuckle may be operated by any suitable means such as a. pullchain 34. When a car is uncoupled, the plunger 22 will open the knuckle 17 into position to be engaged bythe forward end of the lock 2O when the pull-chain 34 is released so that the coupling knuckle is retained in its open position. When the car is uncoupled, the cut-out cock 25 will normally be closed to prevent escape of air from the brake line 23. v vThis means that the cock 29 will be open, but the branch pipe 28 will be closed by the valve 31 for the reason that the knuckle 17 is in open position and the valve 31 will be held closed by its spring. Escape of air from the brake line is therefore prevented bythe cut-out cock 25 and the spring-held valve 31.

In the form of the invention sho-wn in Figs. 1 to 5, when the knuckle is open, valves 25 and 31 are closed and valve 29 is open.

When two cars are brought together, the knuckles 17 will be closed by the impact of the cars and the spring lock 20 will automatically lock the knuckles in their closed position.'- The action of the spring 21 is quicker than the rebound of the cars so Vthat the couplers are locked together before they have time to separate on rebound. At the same time that' the knuckle 17 is closed, its tail piece 19 will engage the valve stem 32 and open the valve 31. This permits escape of air through the branch pipe 28 to atmosphere which will cause the brakes on the train to be set and prevent any further movement of the train until the valve 25 is opened which closes valve 29, Acompleting the coupling operation. open the valve 25, the train will be held from movement until the valve is opened because so long as the valve 25 is closed, the valve 29 will be openand air will escape through the branch-,pipe 28 and valve 31.

If the attendant fails to When the valve 25 Vis opened, establishing brake line connection between the two coupled cars, Vthe same operation will close the valve 29, thus stopping the escape of air 5 from the branch pipe 28 and permitting the brakes to be released so that the train may be moved. Until this is done, however, it will be impossible to move the train since all of the brakes will be set. The valve may, of course, be operated in any of the usual ways, as, for insta-nce, by a push-button connected with electro-pneumatic operating means such as that shown in my prior Patent #1,223,223, dated April 17, 1919, or #1,381,- 5 852, dated June 14, 1921. Any other suitable operating mechanism for the valve and switch may be used, such as a rod or handle.

In Fig. 6, an arrangement is shown in which the inventionv is applied to a tightlocking coupler intended 'for co-operation with another coupler of the same type or with a coupler not provided with automatic brake line connectors but in which connection of the brake line is secured by means of a flexible hose. In this Fig. 6, whenthe car is uncoupled, the knuckle is open. Pipe 23 is under pressure and valves 25, and 35 are closed, so that no air can escapev from the system` and valve ,29 is open. The construction is similar to that shown in Figs. 1 to 5, inclusive. except that the branch pipe 28 is provided with a three-wav cock 35, one port of which is connected to a exible hose coupler 36. In one position of the three-wav cock 35, the branch pipe 28 is connected with the hose coupling 36 and Vin the other position, the branch pipe 28 is connected withthe valve housing 30. When the form of mechanism o shown in Fig. 6 is coupled with a similar tight-locking coupler. the three-way cock 35. which is closed. prevents the escape of air through the fiexible hose coupler 36.l so that the operation is exactly the same as that previously described in connection with Figs. 1 to 5.

If, for any reason, the three-way cock is turned to a position to connect the by-pass with the flexible hose coupling when the hose 0 is not coupled, air will escape through the fiexible hose coupling and set the brakes so that the train cannot be operated until the three-way cock is again turned to its closed position. 5 Now, if the coupler of Fig. 6 is connected with a car equipped with the old form of coupler head and flexible hose connections, the flexible hose 36 will have to be coupled with the flexible hose of the coupled car, and as the cock is closed, the passage through the branch pipe 28 is open so that the brake line is connected through the branch pipe 28 and hose coupler 36. Before the train can be moved, the three-way cock 35 must U be operated to closethe passage to the valve 30 and open the passage to the flexibl'ehose 36. through the valve 30 and the brakes will apply andv cannot be. released. .v If the cock 25 shouldV accidentally be operated, air would escape through the butt end Contact 24 and the train cannot be moved. It is apparent therefore thatbefore the train can be moved, proper connection must be established be-v tween the brake 'lines of the coupled cars through the'hose couplings. In this construction, the valve 25 is closed and the drum switch 26 is open-circuited, thus de-ener-` gizing the exposed electricalcontacts on the coupler head. Since there are no co-operat` ing electrical contacts on the coupled car, this disconnection is desirable as otherwise live contacts would be exposed.

It is apparent thereforek that whether the Y coupler shown in Fig. 6 is connected with. a car equippedwith a like coupler or with a car equipped with flexible hose connection, it will be impossible to operate the train until proper communication between the brake lines o-f the two cars has been established.

Fig. 7 shows an adaptation of the invention Vto cars having any form of mechanical coupler and having any form of connection for the brake line pipes. The illustration shows a Janney type coupler 37 and a flexible hose connection 38 for the brake line pipe 23. A three-way cock 39 is arranged between 'the brake line pipe 23 and the flexible hose connection 38 and the thirdport of the three-way cock is connected with a pipe 40 which communicates with a valve housing 41similar to the housing 30. The valve housing 41 is provided with a spring-held valve similar to the valve 31 and a plunger 42 similar to the plunger 32. Theplunger 42 projects through the contact face of the buring platform .43, as shown in Fig. 8. When two cars are coupled together, the buffing platform 43 engages the platform 44 ofthe coupled car, pressing vthe plunger 42 inwardly and opening the valve in the housing 41. Vhen two cars thus equipped are coupled together, if the cutout cock is left closed,air will escape through the pipe and the valve 41 since the plung er 42 will be moved inwardly to open the u valve 41. lThis will `set the brake so that the cars cannot be moved until the three-way cock 39 is opened to permit communication between the brake line pipes of the ytwo cars through the flexible hose 38. If the hose are not properly coupled up, air will escape from the hose so that the cars cannot be moved. It will be apparent that the valve for controlling the escape of air fromthe branch pipe may be operated by any parts which are affected by the proper coupling of the cars. In the forms of the invention shown in Figs. 1 to 6, inclusive, for instance, the control valve could be mounted on the bulfing platformslinstead of in the path of the coupling If this is not done, air will escapev Aio knuckles. The only essential feature is that the valve shall be locatedso that itwill be opened when the cars are coupled together and closed when the cars are uncoupled.

Fig. 11 shows the control valve located on the guard arm of the coupler. lVhen the valve is in this position, it is not necessary for the knuckles to be open on the rends of the train since the control valve is operated by cont-act with a co-operating coupler and not by its own knuckle. i y

Figs. 1 to 6, inclusive, show the control valve operated by the knuckle of the coupler and the object of this is to compel the knuckles on both ends of the train to be open ready to couple at all timesso that in case of collision of two trains, the couplers will automatically couple and assist in preventing telescoping, sandwiching and overturning of cars, as more fully described in my prior Patent 1,660,733, Feb. 28, 1928. It is also apparent that if collision occurs, the. closing of the knuckles would open the controlling valves on both couplers and apply the brakes on both trains inasmuch as the cut-out cocks at the ends of. both would be closed.

As shown in Fig. 10, the end of the brake line pipe 23 is open so that communication is established with the co-operating brake line upon impact of the cars and the portion of the brake line beyond the cut-out cock is left -open to atmosphere when the cars are unlbe no circulation of steam through this part of the steam line. There will be a tendency therefore for the steam to condense at this point in the line, causing an accumulation of water which might freeze or otherwise interfere with the heating of the rear car or carsof the train. To free the pipe from condensed vapor, a trap 50 is connected with the steam line 45 at each end of each car and the traps are provided with float valves 51 which are automatically lifted by water accumulating in the traps, thus draining the water from the traps. It is not essential that any of these traps except the one at the end of the train be permitted to operate when the locomotive or steam supply is connected and for this reason the traps are all provided with valves 52 arranged to close the passage between the steam pipe 45 and the traps. Springs 53 are provided for opening the valves 52. The upper end of each valve bears upon a diaphragm 54 having a chamber 55 above the diaphragm connected by a passage 56 with a portion ofthe brake line pipe 23 beyond the cut-out cock.

lllhen the cars are coupled up in the train and air under pressure is admitted to the l brake line pipe 23, all of the valves subjected to this pressure will be closed and any moisture condensing in the steam pipe will be carried along to the rear end of the train. The valve 52 at the rear end of the train, however,

will be open for the reason that the end of `It is notedthat the conduit 56 connects with the air brake line 23 at a point above the bottom of the pipe so that moisture will not enter the conduit-from the air brake line.

lVhen the cars have been disconnected from the locomotive and set away in the yards, the air pressure will be o the diaphragm 54 and the traps will all operate so that the steam lines of all of the cars will be drained. The steam pipe connections between the trains are at the lowest portion of the steam heating system,'as will be apparent from the drawings` so that the steam traps in these pipes will drain the entire heating systems. It is apparent that when the locomotive is detached, there will still be air in the brake pipes but in practice this air will leak out and cause a reduction of pressure that will allow the traps to operate in the same time it takes for steam to condense in the steam pipe. When it is desired to separate two coupled cars, the normal operation is to close the valve 25 and open the switch 26 before moving the cars apart. This operation will open the valve 29 and permit the escape of air through the valve 31, setting the brakes on the coupledcars. As-soon as the lock 2O is withdrawn, however, the spring-held plunger 22 will swing the knuckle toward its open position. There is sulicientclearance in the contour of the coupler heads to permit a slight angular movement of the knuckles without separation of the cars. This movement of the knuckles will bring the cam. surface 33 past the valvek stem 32 and permit the valve 31 to close againstits seat, thus checking the escape of air and allowing the release of the brakes.' The cars may then be separated. Although it is desirable in some cases to so locate the valve stem 32 relative to the knuckle that the initial movement of the knuckle within the contour of the connected coupler will permit the valve 31 to close. this is not essential to the separation of the cars for, even though the valve 31 is open, the engineer can move his air brake valve to charging position which will supply suflicient air to enter the system to overcome the reduction in pressure due to escape through the valve 31 and lliA thus release the brakes to permit the cars to be separated. Where this method of operation is used, the opening in the seat for the valve 31 will be of proper size to set the brakes when the engineers valve is in its running position, but will be small enoughv so that when the engineers valve is in charging po sition, the reduction in pressure due to the escape of air through the valve 31 will be overcome by the airintroduced into the system and the brakes vWill be released.V This method of separating the cars will be employed Where the valve stem 32 is controlled by the position of the cars rather than by the position of the coupling knuckle, as in Figs. 8 and9.

I claim:

l. The combination with cars having brake lines and brake line connectors, of means for mechanically coupling said cars, and means automatically placed in afperable condition by the mechanical coupling means of the cars for preventing movement of said cars if said brake line is not properly conditioned for train operation.

V2. The'combination with cars having brake lines and brake line connectors, of means for mechanically coupling said cars, valves for closing said brake lines, and means automatically placed in operable condition by mechanical coupling of said cars and operatively connected with said valves for opening a brake line to atmosphere sulicientlyv to set the brakes of the cars whenever said cars are coupled and a brake line valve is closed.

3. The combination with cars having brake lines and brake line connectors, of means for mechanically coupling said cars, a valve for closing a brake line, abranchpassageto atmosphere for said brake line of suilicient capacity to set the brakes on said cars When said passage is open, a control valve for said passage, and means for operating said control valve, said last named means being automatically operated by mechanical coupling of the cars to open said control valve to atmosphere and to hold said control valveropen so long as said cars are coupled together and additional means for controlling venting of said brake line through said branch passage.

4. The combination with a brake line for a car,- of a cut-out valve for closing said bra-ke line, means for connecting 'said brake line with the brake line of a coupled car, and means including a valve operable by the mechanical coupling means of said cars for opening said brake `line to atmosphere suiiiciently to set the brakes on saidY car When said firstlnamed valve is closed and additional means controlling said opening of said brake line to atmosphere.

5. The combination nwith a brake line for a car, of a valve for closing said brake line,

said brakel line having a branch lpassage to 05S atmosphere ofL sufficient capacity to set the brakes of the cars when said passage is open, a control valve for said passage arranged to be opened when said valve is closed, a valve biased to closed position for closing said branch passage, and .means operable by the coupling together of two cars for opening to atmosphere from said three-Way valve, and

means operated by mechanical coupling of tivo `cars for opening said spring held valve. 7 The combination With an air brake line for a car, of a valve orclosing said line, a' branch passage from said lme to atmosphere 1 of sufficient capacity to set `the car brakes When said passa-ge is open, means for closing said passage, means operated by the coupling of said car to another car or'opening said closing means and holding said closing means open so long as said cars-are coupled together' and additional 'means for controlling the' venting of said air brake line through said branch passage. y Y

8. The combination With anair brakeV line for a car, of a valve for closing said air brake line', a branch from said air brake line to at-` mosphere of sufficient capacity to set the Car brakes When said branch is open, means forV closing said branch When said valve is opened loo and for opening said branchvvhen said valve is closed, supplemental means for closing said branch, and means operated by mechanical coupling of one car with another for automatically operating said supplemental means and opening said branch to atmosphere.-

9. The combination with a car coupling having a coupling knuckle, of a train line, av valve for closing said train line, a branch for said train line, means 'for closing said branch, means operated by said coupling knuckle for opening said closing means and additional means for controlling said branch.

10. The combinationvith a car coupler having a coupling knuckle, of an air brake line, a valve for closing said air brake line, a branch passage for said air brake line to bleed the same, means for opening said branch passage to atmosphere When said valve isv closed and for closing'said branch when said 'y valve is opened, ausupplementall spring held valve for closing said branch, and means 0perable by said coupling knuckle for opening automatically opening said knuckle When released by said lock, an air brake line, a valve for closing said air brake line, a branch on the car side of said valve from said air brake line, a .Valve for said branch interlocked With said branch and means o erable b'1 said knuckle for opening said spring held valve when said knuckle is in coupled position.

12. A car having a coupling knuckle, an

air operated brake system, means including a valve operated by the closing of the knuckle to vent the brake pipe system to atmosphere and to close said vent when said knuckle is opened and additional means for controlling said venting of the brake pipe system.

13. In combination a car, car coupler, an air brake system, means including a valve operated by the mechanical coupling means for the car to vent said air brake system to atmosphere and additional means for controlling said venting of said air brake system.

14. In combination a coupler having a coupling knuckle, an air brake line, a valve for closing said air brake line, a lock for holding said knuckle closed,means for automatically opening said knuckle When said lock is released, and means including a. valve interlocked with said lirst named valve, and a supplemental valve operated by said knuckle for releasing` the air from said air brake line When vsaid first named valve is closed and said knuckle is closed, to require the knuckle at the end of the train to be held in open position in readiness to engage the knuckle of a coupler impacting therewith and to eifect operation of the brakes on closing of said knuckle.

15. The combination With cars having brake -lines and brake line connectors, of means for mechanically, coupling said cars, a valvetor closing a brake line, a branch to atmosphere for said brake liney of suliicient capacity to set the brakeson said cars When said branch is open, means interlocked With said valve for closing said branch when said valve is open and for opening said branch When said valve is closed, supplemental means for closing said'branch and means automatically operated by the coupling of said cars to actuate said supplemental means and open said branch to atmosphere.

16. The combination with cars having brake lines and brake line connectors, of means for mechanically coupling said cars, a valve for closing a brake line, a branch passage to atmosphere for said brake line of sucient capacity to set the brakes on said cars When said passage is open, a valve interlock-ed with said Iirst-named valve for controlling said branch passage, supplemental means for closing said branch to'atmosphere and means automatically operated by mechanical coupling of the cars for opening said supplemental means and holding it open so long as the cars remain' coupled together.

17. The combination With a car having air brake mechanism including a brake line and a brake line connector, or' ymechanical 'coupling mechanism for said car, a cut-out valve for closing said brake line, a branch for con- 18. The combination With a car having air A f brake mechanism including a.. brake line and a brake line connector, ot' mechanical coupling mechanism for said car, a cut-out valve for vclosing said brake line, a branch to atmcsphere for said brake line of sulicient capacity When open to set the brakesof said car, al control valve for said branch interlocked With said cut-out valve and open when saidcut-out valve' is closed and closed when said cut-out valveis open, and a supplemental valve for closing said branch held in open position by the mechanical coupling mechanism When two cars are coupled together.

19. The combination With cars having an air brake system comprising a brake line and brake line connectors, of means for mechanically coupling said cars, a cut-out valve for closing said brake line, and means automatically operated by mechanical coupling of the cars for actuating said air brake system to set the brakes on some of said cars if said cut-out valve is closed.

20. The combination with an air brake line for a car adapted to be controlled by an engineers valve, of a cut-out valve for closing said line, a branch passage from said line Vto atmosphere of sulicient capacity as related to the capacity of the engineers valve to Vset the car brakes when said branch passage is open and the engineers valve is in running position, but of insu'icientcapacity to set the brakes when the engineers valvebeing arranged to close said branch by theslight movement of said knuckle toward its open position permitted by the contour of thev branch, a mechanical coupler for said car having a coupling knuckle and means operated by said knuckle for opening said valve when said knuckle is in coupled position, said means being arranged to permit said valve to close when said knuckle has moved a predetermined amount toward its open position.

23. The combination with a car having an air brake line, of a valve for closing said line, a branch passage to atmosphere for said line, a valve for closing said passage, mechanism for mechanically coupling said car, and means automatically operated by mechanically coupling said car for opening said last named valve when said car is coupled with another car and for holding said valve openso long as said cars are coupled, said means being movable to a position, however, permitting said last named valve to close when the coupling mechanism for said car is unlocked and before said car is moved away from the coupled car andadditional means for controlling said branch passage.

24. rl`he combination with cars having brake lines and brake line connectors, of

means for mechanically coupling said cars,

said means including a control device automatically operable by mechanical coupling of the cars when the brake line is not properly conditioned for train operation to apprise the trainmen of this fact.

In testimony whereof I have signed my name to this speciiication this 13th day of March A. D. 1930.

CHARLES H. TOMLINSON. 

